valve cover Q

[pug]

I have a 1990 2.5. There is thee holes on the top outside of the valve cover.1 for the oil cap, 1 for the pcv, and 1 for something that goes from vale cover to air box. My question is the baffel or what ever it is inside of the valve cover broke off. The one hole that goes to air box. It was hitting the rocker arms so i took it out the knocking sound is gone now i have oil everywere. Can i block this line off what is its purpose anyway.

[Eagle]

You can't block it off. The crankcase is a closed system, and it needs ventilation. The PCV is an outlet valve -- crankcase fumes are sucked up through the PCV and into the intake manifold, from where they go to the engine and get burned. The "makeup air" has to come from somewhere, and that's what the line you are referring to is -- the intake. It draws air through the air filter so you're not sucking dirt and dust into the crankcase.

[pug]

Thanks for info. Is there any way to fix this problem are do i have to buy a new valve cover.

[Eagle]

Do you have the original, plastic valve cover, or do you have metal?

[pug]

I have a plastic valve cover.

[Oizarod115]

you can replace the plastic valve cover for cheap online, and chances are it probably needs one anyways, they tend to break out around the bolt holes. only thing is you'll have to wait for shipping on it.

[pug]

Just orderd one $50. includes shipping from quadratrac.

[Oizarod115]

Just orderd one $50. includes shipping from quadratrac.

good deal, we had to do that for a guy with a 90 YJ a couple weeks back cause his was busted out/not sealing.

 

make sure to get a gasket (i would think it comes with one) but don't try to just RTV it down, seen that trick tried... it doesn't work. 8)

[vaquaro]

Just orderd one $50. includes shipping from quadratrac.

good deal, we had to do that for a guy with a 90 YJ a couple weeks back cause his was busted out/not sealing.

 

make sure to get a gasket (i would think it comes with one) but don't try to just RTV it down, seen that trick tried... it doesn't work. 8)

:hmm: I beg to differ .RTV was the oem gasket , note that shoulder bolts are used to accommodate this method (you'll need to get new bolts for the pre-made gasket )If you do the RTV (Permatex Copper is the best) correctly it works great , clean surfaces and patience are key . Lay down a 3/8" bead on the new valve cover , let it fully cure (over-nite ) . Apply a thin wet coat of RTV to cylinder head & previous RTV bead on vc , install vc ,bolts finger tight ,wait 10 min. ,torque bolts to spec. ,wait 15-30 min. ,start motor and check for leaks (unlikely ) :thumbsup: